"Poi" is the Maori word for "ball" on a cord

The Poi was used, many years ago, by the indigenous Maori people of New Zealand to increase their flexibility and strength in their hands and arms as well as improving coordination.

Wahine (female) dancers perform the Maori Poi, a dance performed with balls attached to flax strings, swung rhythmically.

The Poi dance was originally used by the Maori women for keeping their hands flexible for weaving and by the men for strength and coordination required during battle. Poi are also used as a training aid for other ancient weapons like the Mere or Patu (Short club)

I posted this a while back also - A friend at work was doing it and taught me - I have been doing it for over 2 yrs now and I already had good speed and coordination but it took me to the next level - it also helps develop both sides of the brain - balance defense speed and offense - basically it develops every thing needed for boxing - I know I am not the only one doing this here - maybe you know it by a different name - here is their site for more info http://homeofpoi.com/ - this site also has poi lessons

This is what I do before and after a workout to warm up and warm down.